Journal of Epidemiology




Volume 31, Issue 1-12 (2021)

Issue 12 (December 2021)
Issue 11 (November 2021)
Issue 10 (October 2021)
Issue 9 (September 2021)
Issue 8 (August 2021)
Issue 7 (July 2021)
Issue 6 (June 2021)
Issue 5 (May 2021)
Issue 4 (April 2021)
Issue 3 (March 2021)
Issue 2 (February 2021)
Issue 1 (January 2021)

Volume 31, Issue 12 (December 2021)

Night Work, Rotating Shift Work, and the Risk of Cancer in Japanese Men and Women: The JACC Study
  • Rotating shift work was significantly associated with increased risk of esophageal cancer among Japanese men.
  • Japanese men who reported rotating shift work tended to experience a higher risk of prostate cancer compared with men working in the daytime.
  • Night work and rotating shift work were not related to the risk of all-cause cancer in either sex.
The Estimated Prevalence and Incidence of Endometriosis With the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC): A National Population-Based Study
  • We estimated the prevalence and incidence of endometriosis using the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC), which correspond to approximately 1 million individuals selected randomly from the Korean population from 2002 to 2013.
  • The age-adjusted prevalence rate of endometriosis also increased from 2.12 per 1000 persons (95% CI, 2.01-2.24) in 2002 to 3.56 per 1000 persons (95% CI, 3.40-3.71) in 2013.
  • The age-specific incidence rate of the age group 15-24 increased steeply, while the incidence rate of the age group 40-49 decreased significantly over 11 years.
Effect of Secular Trend, Age, and Length of Follow-up on Optimum Body Mass Index From 1985 Through 2015 in a Large Austrian Cohort
  • It has been shown that the BMI optimum in the BMI all-cause mortality relationship is influenced by age and length of follow-up.
  • Also, a possible secular trend in the BMI optimum has been of recent debate.
  • All these factors have now been simultaneously analyzed in a large Austrian dataset with 30-year follow-up.
  • Age and length of follow-up had a pronounced but interactive effect on the BMI optimum.
  • While controlling for age and length of follow-up, the BMI optimum increased only slightly from 1985 to 2015.
The Association Between Fathers’ Self-assessment of Their Own Parenting and Mothers’ Recognition of Paternal Support: A Municipal-Based Cross-Sectional Study
  • Fathers’ household work and parenting time showed significant differences among four groups classified by both parents’ recognition of paternal parenting and support.
  • Maternal mental health condition and pregnancy intention were significantly associated with the discrepancy (paternal recognition of paternal parenting: PRPP + and maternal recognition of paternal support: MRPS −) compared with positive agreement.
  • Paternal mental health condition and marital satisfaction were significantly associated with the discrepancy (PRPP − and MRPS +) compared with positive agreement.
  • Maternal mental health condition was significantly associated with the negative agreement compared with positive agreement.
  • For enhancing paternal parenting participation, grasping both parents’ profiles in clinical practice is essential.
High-sensitivity C-reactive Protein and Regression of Low-grade Squamous Intraepithelial Lesion: The Role of Low-grade Inflammation in Cervical Carcinogenesis
  • This is the first cohort study to verify an association between the host inflammation status and spontaneous LSIL regression.
  • A higher level/quartile of hs-CRP was significantly associated with a lower rate of regression (for quartile 4 vs. quartile 1, inverse HR 1.33; 95% CI, 1.04-1.69; P for trend=0.028).
  • Our outcomes suggest tha low-grade inflammation could affect the natural course of LSIL and hs-CRP level, a low-grade inflammation marker, could play a role as an independent predictor of cervical carcinogenesis.
Associations of Body Mass Index, Weight Change, Physical Activity, and Sedentary Behavior With Endometrial Cancer Risk Among Japanese Women: The Japan Collaborative Cohort Study
  • Body mass index over 23.0 kg/m2 were linearly increased risk of endometrial cancer. The hazard ratios (95% confidence interval) per 5 kg/m2 increase was 1.80(1.28-2.54).
  • Weight increment ≥+5 kg since age 20 was associated with a 2-fold higher risk of endometrial cancer.
  • Compared to who were mostly sitting at the worksite, being active at the worksite were at lower risk of endometrial cancer.
  • Hours of physical exercise, daily walking, and TV viewing were not associated with endometrial cancer risk.
Women With Osteoarthritis Are at Increased Risk of Ischemic Stroke: A Population-Based Cohort Study
  • We identified 13520 women with OA newly diagnosed in 2000-2006 and 27033 women without OA in the comparison cohort.
  • The incidence rate of ischemic stroke in the OA cohort was 1.5-fold greater than that in comparisons.
  • The nest case-control analysis showed that hypertension developed was 2-fold greater in the stroke cases than controls.
  • The ischemic stroke risk was associated with hypertension and atrial fibrillation.
  • Ischemic stroke was not associated with the medication of NSAIDs and aspirin.
Social Predictors of Continued and Indoor Smoking Among Partners of Non-smoking Pregnant Women: The TMM BirThree Cohort Study
  • Most smoking partners of non-smoking pregnant women continued to smoke after becoming aware of the pregnancy, and one-third of them smoked indoors.
  • Workplace secondhand smoke exposure was associated with continued and indoor smoking after pregnancy awareness among partners of pregnant women.
  • Women’s quitting smoking after pregnancy awareness was associated with decreased risk of continued smoking among partners of pregnant women.
  • Women’s quitting smoking after pregnancy awareness was associated with increased risk of indoor smoking among continued smoking partners.
  • Lower education was associated with increased risk of indoor smoking among continued smoking partners.
The Association of Work-related Stress According to the Demand–Control Model With Aggravation of Pre-existing Disease During the First State of COVID-19 Emergency in Japan
  • Eleven percent of the working participants with pre-existing diseases reported disease aggravation during the first state of COVID-19 emergency in Japan.
  • Job strain, characterized by high job demand and low job control, was associated with aggravation of pre-existing disease.
  • The pathway through which aggravation of pre-existing disease might occur during a short period of time in workers with job strain need further elucidation.
Short Communication
Italians Do It...Less. COVID-19 Lockdown Impact on Sexual Activity: Evidence From a Large Representative Sample of Italian Adults
  • COVID-19 lockdown restrictions drastically altered people's day-to-day life and impacted on lifestyle habits and behavioural risk factors.
  • A cross-sectional survey was conducted on a representative sample of the Italian general population to explore how sexual activity was impacted by the COVID-19 lockdown.
  • Over one third of Italians reported to have changed their sexual activity during lockdown.
  • When focusing on cohabitants, decreased sexual activity was more frequently reported by men, younger, more educated subjects, subjects living in smaller houses, and those reporting longer time spent outdoor before the lockdown.
Statistical Data
Trend in Cancer Incidence and Mortality in Fukushima From 2008 Through 2015
  • Cancer incidence for Fukushima residents before and after the disaster on March 11, 2011 is reported using the data from Fukushima Cancer Registry.
  • The corrected incidence data from the Fukushima Cancer Registry from 2008 to 2015 had sufficient quality comparable to other population-based registries.
  • We observed similarities in incidence and mortality between Fukushima and its neighboring Tochigi Prefecture from 2008 to 2015, except for thyroid cancer.
  • Our results provide basic statistics for subsequent researchers to assess the relationship between the disaster and cancer incidence in Fukushima.
Study Profile
Study Profile of the Japan Multi-institutional Collaborative Cohort (J-MICC) Study
  • The J-MICC Study was launched in 2005 to examine sgene–environment interactions in lifestyle-related diseases including cancers among the Japanese.
  • From 2005 to 2014, a baseline survey included 92,610 adults from 14 study regions from 12 prefectures across Japan.
  • This large-scale, population-based, genome-cohort is expected to be a valuable resource in providing evidence to support longer healthy lives.


Volume 31, Issue 11 (November 2021)

Relative Effects of Demographic, Psychological, Behavioral, and Social Factors on the Initiation and Maintenance of Leisure-time Physical Activity: Results From a Confirmatory Path Analysis in a Longitudinal Study
  • The present study found an initiation- and maintenance-specific results from a hypothetical determinant model that can assess the direct and indirect effects of each determinant on physical activity through different pathways at each phase.
  • Age, education, chronic diseases, smoking, depression symptom, and self-rated health had significant associations with both initiation and maintenance phases.
  • Income and social support were initiation-specific determinants in women and had significant indirect effect on both phases of LTPA.
  • Waist-to-hip ratio and stress was maintenance-specific determinant, and the effect of stress was only found in women.
  • The indirect effect of most factors in the hypothetical model was estimated to contribute 10-20% of the total effect on LTPA.
Overweight and Hypertension in Relation to Chronic Musculoskeletal Pain Among Community-Dwelling Adults: The Circulatory Risk in Communities Study (CIRCS)
  • We examined an effect modification by hypertensive status in the associations between overweight and chronic low back/knee pain.
  • Overweight was associated with overall chronic knee pain regardless of its severity and hypertension status.
  • Overweight was primarily associated with severe chronic low back pain among non-hypertensives.
  • Hypertension may attenuate the association between overweight and chronic low back pain.
Prevention Measures for COVID-19 and Changes in Kawasaki Disease Incidence
  • Kawasaki disease is an acute systemic vasculitis of unknown cause and is suspected to be triggered by infectious diseases.
  • The prevention measures for coronavirus disease 2019 (COVID-19) have reportedly reduced transmission of certain infectious diseases.
  • Registration datasets in one of Japanese prefectures retrospectively showed a significant reduction in Kawasaki disease during the COVID-19 pandemic.
  • This study provides new epidemiological evidence for the notion that Kawasaki disease is triggered by major infectious diseases in children.


Volume 31, Issue 10 (October 2021)

Association Between Social Isolation and Smoking in Japan and England
  • Social isolation is associated with current smoking status.
  • Little is known about varying associations of social isolation with smoking in different countries with tobacco control policies.
  • Older people who were not socially isolated were more likely to quit smoking in England than in Japan, explained by the strict tobacco control policies.
Are Japanese Women Less Physically Active Than Men? Findings From the DOSANCO Health Study
  • We aimed to compare Japanese men and women’s time spent in sedentary behavior and different intensities of physical activity.
  • The co-dependence of activity behaviors was taken into account.
  • Compared to men, women had less time spent in sedentary behavior and more time spent in light-intensity physical activity.
  • There was no significant gender difference in time spent in moderate-to-vigorous physical activity. Japanese women are more physically active than men when all intensities of activities are considered.
Prevalence and Associated Factors of Pathological Internet Use and Online Risky Behaviors Among Japanese Elementary School Children
  • We aimed to investigate the prevalence of pathological Internet use (PIU) and online risky behaviors among elementary school children.
  • The prevalence of PIU was 4.2% and online risky behaviors such as spending money online and having met strangers were not rare among children.
  • Besides children’s unhealthy lifestyles, PIU was associated with no rules at home, no close friends in real life, and no child-parent interaction.
  • Increasing child-parent interaction and helping children develop close friendships in real life are effective deterrents to PIU.
Cultural Engagement and Incidence of Cognitive Impairment: A 6-year Longitudinal Follow-up of the Japan Gerontological Evaluation Study (JAGES)
  • We used cohort data from the Japan Gerontological Evaluation Study (JAGES) involving 44,985 older Japanese adults collected from 13 municipalities.
  • Cognitive impairment was assessed by the nationally standardized dementia scale proposed by the Japanese Ministry of Health, Labour and Welfare.
  • Reading books, magazines, and/or newspapers was protectively associated with the risk of cognitive impairment.
  • Engagement in craft or painting was also significantly correlated with a lower risk of cognitive impairment.
  • Increasing opportunities for community participation in these forms of cultural engagement through clubs and circles may be effective in preventing dementia.


Volume 31, Issue 9 (September 2021)

Validity Assessment of Self-reported Medication Use for Hypertension, Diabetes, and Dyslipidemia in a Pharmacoepidemiologic Study by Comparison With Health Insurance Claims
  • Self-reported medication use for lifestyle-related disease (hypertension, diabetes and dyslipidemia) showed high validity on matching with health insurance claims using three- and six-month fixed time windows, although self-reported medication use for dyslipidemia showed lower sensitivity than the other medications.
  • Males without high education and those who currently smoke cigarettes were associated with discordance which affected sensitivity in self-reported medication use for dyslipidemia.
  • Self-reported questionnaires on medication use for lifestyle-related diseases could be a valid measure to capture regular medication users in a cohort study.
Overall and Cause-Specific Mortality in Patients With Type 1 Diabetes Mellitus: A Population-Based Cohort Study in Taiwan From 1998 Through 2014
  • Diabetes, cancer, and circulatory diseases were the leading causes of death in type 1 diabetes in Taiwan, 1998-2014.
  • Type 1 diabetes was significantly associated with elevated all-cause SMR for at 4.16.
  • Cause-specific SMR was mostly elevated for diabetes (16.45), renal disease (14.48), followed by liver disease (4.91) and infection (4.59).
Emergency Dispatches for Suicide Attempts During the COVID-19 Outbreak in Okayama, Japan: A Descriptive Epidemiological Study
  • We evaluated emergency dispatches during 6-month periods (March–August) of 2018, 2019, and 2020 during the COVID-19 outbreak in Okayama, Japan.
  • We found that emergency dispatches were decreased in 2020 compared with the previous 2 years, while the number and proportion of emergency dispatches related to suicide attempts increased.
  • This increase was more pronounced among women and those aged 25–49 years.


Volume 31, Issue 8 (August 2021)

Special Article
Using Propensity Scores for Causal Inference: Pitfalls and Tips
  • A general introduction to causal inference and propensity score methods is provided.
  • Relative advantages of propensity score methods over multivariable regression are discussed.
  • Two popular propensity score methods — matching and inverse probability weighting — are compared.
  • The alternative methods rely on similar assumptions for identification, with subtle differences.
  • The alternative methods make different modeling assumptions and answer different questions.
Mumps-Related Disease Burden in Japan: Analysis of JMDC Health Insurance Reimbursement Data for 2005–2017
  • Incidence rates of mumps and its complications in Japan were assessed using 2005–2017 health insurance reimbursement data for >5 million individuals.
  • The annual incidence rate of mumps was highest in those aged 0–5 years, followed by those aged6–15 years, and higher in females than in males.
  • The overall incidence of mumps-related complications was 2.5-times higher in males than in females and the most common complication was orchitis.
  • Increasing mumps vaccination coverage is urgently needed to reduce the incidence of mumps related complications, particularly long-lasting complications.
The Clustering of Health-Related Behaviors in the Adult Japanese Population
  • Health-related behaviors cluster in the Japanese population that differ according to gender.
  • Men and women undertook inadequate levels of physical activity and a large proportion of men exceeded recommended levels of alcohol consumption.
  • Cluster membership related to age for both genders and amongst men, it was associated with income and health status.
  • These results can inform the development of person-centered lifestyle interventions and health-related behaviors policies.
Impact of Rotavirus Vaccines on Gastroenteritis Hospitalizations in Western Australia: A Time-series Analysis
  • Following rotavirus vaccination introduction, up to 79% decline in rotavirus-coded hospitalisation rates among non-Aboriginal children aged <5 years.
  • Among the Aboriginal population, up to 66% decline in rotavirus-coded hospitalisation rates were observed among children aged <2 years.
  • No evidence of herd immunity among adults aged ≥45 years from the infant vaccination program was observed.
  • The differential impact of the vaccine in Aboriginal and non-Aboriginal children and increase in burden in older adults warrants further research.
Clinical Characteristics and Risk Factors for Severe Outcomes of Novel Coronavirus Infection, January-March 2020, Japan
  • We summarized 516 incident novel coronavirus infection cases in Japan, along with risk factors associated with severe outcomes.
  • Among cases with outcome data, elderly men and patients with lifestyle-related diseases or lung diseases had higher risk of severe outcomes.
  • Some cases who were hospitalized while asymptomatic still developed severe outcomes; all these cases were >70 years of age.
  • Within the Japanese context, the findings highlight risk factors for severe outcomes and the need for careful monitoring for certain populations.


Volume 31, Issue 7 (July 2021)

Loss of Working Life Years Due to Mortality, Sickness Absence, or Ill-health Retirement: A Comprehensive Approach to Estimating Disease Burden in the Workplace
  • No study has simultaneously assessed disease burden in terms of mortality and morbidity.
  • We developed a new method of quantifying disease burden in the workplace.
  • Mental and behavioral disorders made a considerable contribution to the disease burden due to sickness absence and ill-health retirement.
  • Neoplasms and diseases of the circulatory system made marked contributions to the number of working years lost due to mortality.
  • This method may facilitate corporate management by enhancing our understanding of the disease burden in the workplace.
Changes in Drug Utilization After Publication of Clinical Trials and Drug-Related Scandals in Japan: An Interrupted Time Series Analysis, 2005–2017
  • In Japan, scandals caused by breaches of ethics in medical research and pharmaceutical marketing occurred following the publication of the results of clinical trials of first-generation angiotensin II receptor blockers.
  • The publication of apparently-successful clinical trials was followed by an increase in the use of first-generation ARBs, and the subsequent research-related and marketing-related scandals were followed by a decrease.
  • Going a step further, to the extent that new drugs and other improvements in medical care are generally adopted slowly and cautiously, whereas reactions to unethical behavior and breaches of trust are quick and strong, these lessons from Japan could well be relevant worldwide.
Skipping Breakfast and Subsequent Overweight/Obesity in Children: A Nationwide Prospective Study of 2.5- to 13-year-old Children in Japan
  • Skipping breakfast at 2.5 years was not associated with overweight/obesity at 2.5 and 4.5 years, but was associated at 7 and 10 years, in both sexes.
  • Skipping breakfast at 2.5 years was significantly associated with overweight/obesity at 13 years in boys, but not in girls.
  • Skipping breakfast in early childhood increased overweight/obesity in later childhood, but there may be gender differences at 13 years.
Updated Trends in Cancer in Japan: Incidence in 1985-2015 and Mortality in 1958-2018 - A Sign of Decrease in Cancer Incidence
  • Trends in cancer incidence and mortality in Japan were examined using most recent representative data.
  • The age-standardized rate of all-cancer incidence started to decrease significantly in males and level off in females in 2010, after a long-term intermittent increase.
  • The convergence of an increase in all-cancer incidence was mainly due to the slowing down of prostate and breast cancers in males and females, respectively.
  • The ASR of all-cancer mortality continued to decrease, the main contributing cancer sites of which were still stomach, liver, and male lung.


Volume 31, Issue 6 (June 2021)

Incidence and Mortality of Dementia-Related Missing and Their Associated Factors: An Ecological Study in Japan
  • The incidence rate and mortality rate of dementia-related missing in Japan were 21.72 and 0.652 (per 100,000 person-year), respectively.
  • One increase in the number of public health nurses per 100,000 persons was associated with a 3.2% (1.6–4.9) decrease in the incidence rate.
  • One facility increases in the number of nursing care facilities for older adults per 100,000 persons aged 65-years-old or more was associated with a 7.9% (95% confidence interval, 3.3–12.4) decrease in the incidence rate.
  • A ten percent increase in the proportion of people who live in an urban area was associated with a 20.3% (8.7–33.2) increase in the incidence rate and a 12.9% (5.6–19.8) decrease in the mortality rate.
  • Identified associated factors may be useful for managing or predicting dementia-related missing persons cases and associated deaths.
Widening Socioeconomic Inequalities in Smoking in Japan, 2001–2016
  • Japan is one of the world’s largest tobacco epidemic countries.
  • No studies addressed trends in socioeconomic inequalities in smoking in Japan.
  • Socioeconomic inequalities in smoking widened between 2001 and 2016 in Japan.
  • Smoking is a potential factor responsible for health inequality in the future.
Changes in Smoking Behavior Since the Declaration of the COVID-19 State of Emergency in Japan: A Cross-sectional Study From the Osaka Health App
  • We examined the effect of the COVID-19 state of emergency on changes in smoking behavior, as determinants of both increased smoking and quitting.
  • In our dataset of 5,120 smokers, 32.1% reported having increased the number of cigarettes they smoked and 11.9% reported quitting smoking after the declaration of a state of emergency in Japan.
  • The smokers who changed from cigarettes to heated tobacco products were significantly less likely to quit smoking than smokers who did not change tobacco type.
  • People working from home or living alone were associated with increased smoking.
Short Communication
Mobility Change and COVID-19 in Japan: Mobile Data Analysis of Locations of Infection
  • Mobility in working, nightlife, and residential places had changed before the state-of-emergency declaration due to COVID-19.
  • Mobility reduction in nightlife places was particularly high during the state of emergency.
  • Mobility change in nightlife places was more strongly associated with the outbreak of COVID-19 compared to that in working and residential places.
Study Profile
The Korean Pregnancy Outcome Study (KPOS): Study Design and Participants
  • The KPOS research aims to investigate the risk factors and distribution of adverse pregnancy outcomes.
  • This cohort study included 4195 Korean pregnant women and the main outcome was gestational diabetes mellitus, gestational hypertension, and screening positive for peripartum depression.
  • Among 3565 pregnancy outcomes, 30 miscarriages, 16 stillbirths, and 3519 deliveries reported.
  • The prevalence of GDM, hypertensive disorders, and screening positive of depression during pregnancy and postpartum was 7.0%, 1.4%, 27.8%, and 16.6%, respectively.
  • Future studies on the KPOS data will provide information on determinants of pregnancy-related disorders, and this improve maternal health among Korean pregnant women.


Volume 31, Issue 5 (May 2021)

Does Laughter Predict Onset of Functional Disability and Mortality Among Older Japanese Adults? The JAGES Prospective Cohort Study
  • The link between laughter and functional disability and all-cause mortality was prospectively studied in community-dwelling Japanese older adults.
  • After adjustment for 13 potential confounders, low frequency of laughter was associated with increased risks of functional disability.
  • The inverse association between the frequency of laughter and the risk of all-cause mortality was insignificant after adjusting for all covariates.
  • Frequency of laughter is potentially considered an early indicator of functional disability later on in life.
What Factors Affect the Evolution of the Wife’s Mental Health After the Husband’s Retirement? Evidence From a Population-Based Nationwide Survey in Japan
  • The husband’s retirement modestly worsens his wife’s mental health.
  • The wife’s behavior at baseline substantially affects the evolution of her mental health.
  • The relevance of the “retired husband syndrome” was relatively limited in Japan.
Higher Participation Rate for Specific Health Checkups Concerning Simultaneous Ophthalmic Checkups
  • It had not been shown whether simultaneous ophthalmic checkups influence the specific health checkups’ participation rate.
  • This study showed the significant positive association between the specific health checkups’ participation rate and simultaneous ophthalmic checkups.
  • In this study, fundus photos and ophthalmology consultation, when offered to all applicants, were associated with a higher specific health checkups’ participation rate.
Prevalence and Mortality of Sarcopenia in a Community-dwelling Older Japanese Population: The Hisayama Study
  • The prevalence of sarcopenia defined by the Asian Working Group for Sarcopenia definition was approximately 7% in a community-dwelling older Japanese population.
  • Older subjects and subjects with ADL disability, less regular exercise, and less total energy intake were more likely to have sarcopenia.
  • Sarcopenia was associated with a significant, 2-fold increment in mortality risk after adjusting for potential confounders.
Increase in Body Weight Following Residential Displacement: 5-year Follow-up After the 2011 Great East Japan Earthquake and Tsunami
  • We compared body weight change between survivors relocated to temporary housing and other types of accommodation for up to 5 years after the disaster.
  • The people in temporary housing group experienced significant increases in body weight compared with the people in non-temporary housing group.
  • The significant differences remained after the adjustment for several confounding factors.
  • Living in temporary housing was independently associated with weight gain after the Great East Japan Earthquake irrespective of baseline obesity.
  • The people living in temporary housing should appropriately control body weight to prevent from obesity related diseases in a future disaster.
Trends in Energy Imbalance Gap and Body Weight Status in the Japanese Adult Population: A System Dynamics Approach
  • In Japan, the overall energy imbalance gap (EIG) increased in males over time with a peak around year 1990, but for females it continuously decreased over the past four decades.
  • The overall EIG was small but remained positive for males in 2015, indicating that the prevalence of overweight and obesity will continue to increase at a slower pace.
  • The overall EIG for females started to show a negative value in 2013, indicating that the prevalence of overweight and obesity started to decrease.
  • The dynamics of the EIG were different not only between the sexes, but also among BMI classes.
Association Between Traffic Count and Cardiovascular Mortality: A Prospective Cohort Study in Taiwan
  • Exposure to diesel- or gasoline-engine exhaust contributes to cardiovascular death.
  • Fine particulate matter links traffic exposure and cardiovascular mortality.
  • PM2.5 contributes higher mediation effect for truck-CVD death association compared with CVD mortality associated with exposure to small cars.
Older Adults’ Daily Step Counts and Time in Sedentary Behavior and Different Intensities of Physical Activity
  • We examined how daily step count related to device-based time spent in activity behaviors among older Japanese adults.
  • The co-dependence of activity behaviors was taken into account.
  • Daily step count was related to the relative proportion of time spent in moderate-to-vigorous physical activity.
  • Daily step count was also related to the ratio between light-intensity physical activity and sedentary behavior.
  • Findings are helpful for better aligning pedometer-based data with accelerometer-based data.
Short Communication
Epidemiology of Food Choking Deaths in Japan: Time Trends and Regional Variations
  • Increasing age globally makes people more vulnerable to food choking.
  • We investigated the characteristics of food choking deaths in all Japan, with its regional variations on national level, and its time trends.
  • The number of deaths due to food suffocation was highest on New Year’s Day, frequently occurred at home, and among people aged over 75 years.
  • The total number of cases was around 4000 each year, but the incidence proportion among people over 75 years old has been decreasing recently.
  • Regional variations between prefectures existed: highest in Niigata and lowest in Kyoto (standardized mortality ratio 1.38 and 0.60, respectively).


Volume 31, Issue 4 (April 2021)

Determinant Factors on Differences in Survival for Gastric Cancer Between the United States and Japan Using Nationwide Databases
  • Large differences in five-year relative survival of surgically treated gastric cancer between two countries: 81.0% in Japan and 45.0% in the US.
  • Wide gap can be explained by earlier stage at diagnosis in Japan due to screening and awareness of gastric cancer.
  • Differences in number of lymph nodes examined also play a key role in the wide gap in survival between two countries.
The Effect of Smoking and Sex on the Association Between Long-term Alcohol Consumption and Metabolic Syndrome in a Middle-aged and Older Population
  • This is the first prospective study to examine how smoking status affects the relation of long-term alcohol consumption on risk of MetS and its components by the amount of alcohol after adjustment for various lifestyle factors including diet in prospective design.
  • Light to moderate long-term alcohol consumption was associated with beneficial and associations on MetS and its components whereas heavy alcohol intake appeared detrimental.
  • Smoking status strongly affected the relationship of long-term alcohol consumption with MetS components, particularly hypertriglyceridemia.
Disparities in Bystander Cardiopulmonary Resuscitation Performed by a Family Member and a Non-family Member
  • We assessed who actually performed bystander cardiopulmonary resuscitation (BCPR).
  • We analyzed the population-based out-of-hospital cardiac arrest (OHCA) registry in Niigata City, Japan.
  • OHCA patients witnessed by family were less likely to receive BCPR compared to those witnessed by non-family members.
  • Among the witnessed patients, the proportion of BCPR actually performed by a family member was lower than that performed by a non-family member.
  • Further efforts will be needed to overcome the barriers for family to perform BCPR.
Role of Social Support in the Relationship Between Financial Strain and Frequency of Exercise Among Older Japanese: A 19-year Longitudinal Study
  • We investigated the association between financial strain and frequency of exercise among Japanese older people.
  • We also tested the role of social support in buffering this relationship.
  • Greater financial strain was associated with less frequency of exercise.
  • As financial strain increased, people with more instrumental support engaged in less exercise than people with less support.
  • These associations were observed among females, but not among males.
Population Attributable Fractions of Modifiable Risk Factors for Nonsyndromic Orofacial Clefts: A Prospective Cohort Study From the Japan Environment and Children’s Study
  • This study reported the population attributable fractions (PAFs) of modifiable risk factors for nonsyndromic orofacial clefts in Japan.
  • Among cleft lip with or without cleft palate (CL±P) cases, non-use of a folic acid supplement had the highest PAF, followed by maternal active and passive smoking.
  • We failed to show a significant association between variables. However, the current results of CL±P support the previous evidence.
Associations of Education With Overall Diet Quality Are Explained by Different Food Groups in Middle-aged and Old Japanese Women
  • We found positive associations of education with a diet quality score consisting of selected seven components in middle-aged and older Japanese women.
  • The associations were mainly explained by different foods, namely ‘milk’ in middle-aged women and ‘sodium from seasonings’ in older women.
  • The associations were independent of lifestyle and neighborhood variables in both groups.
  • The present finding may help inform the development of a public health policy to reduce disparity of diet quality by education.
Physical Fitness and Dyslipidemia Among Japanese: A Cohort Study From the Niigata Wellness Study
  • Grip strength relative to BMI was inversely associated with the risk of dyslipidemia among both men and women.
  • Vertical jump relative to BMI was also inversely associated with the risk of dyslipidemia among both men and women.
  • There was no association of single-leg balance, forward bending, and whole-body reaction time with dyslipidemia.
Short Communication
Association of Eating Alone With Depression Among Older Adults Living Alone: Role of Poor Social Networks
  • We hypothesise that the known association of eating alone with depression may be confounded by social network size.
  • Eating alone and poor social network were independently associated with greater depression in older adults living with others.
  • Poor social network was associated with greater depression symptoms irrespective of eating style in older adults living alone.
  • Even when eating and living alone, older adults with decent social networks are more likely to be mentally healthy.


Volume 31, Issue 3 (March 2021)

A Prospective Cohort Study of Bedroom Warming With a Heating System and Its Association With Common Infectious Diseases in Children During Winter in Japan
  • The use of a heating system in the bedroom is strongly associated with a decrease in the frequency of catching cold in children.
  • Children who did not use a heating system in the bedroom are more likely to take sick leave from school or nursery.
  • Relationship exists between a heated bedroom and number of hospital visits due to cold.
  • Children who did use a heater in the bedroom had significantly lower odds of being infected with influenza and having diarrhea with vomiting.
Differential Effect of Polymorphisms on Body Mass Index Across the Life Course of Japanese: The Japan Multi-Institutional Collaborative Cohort Study
  • There was a significant association between three body mass index (BMI) traits and polymorphisms in or near FTO, BDNF, TMEM18, HS6ST3, and BORCS7.
  • The BMI-related loci discovered in European ethnicities also have significant association in Japanese population.
  • The loci of association with current BMI and BMI change were similar, in contrast, unique associated loci were identified in BMI at 20 years old.
  • Our study indicated that the genetic effects on BMI by these BMI-associated loci may vary across the life course via different pathways.
The Impact of Hypertension Definition Based on Two-visit Strategy on Estimate of Hypertension Burden: Results From the China Health and Nutrition Survey 1989–2011
  • Based on the measurements from the China Health and Nutrition Survey (CHNS1989–2011), one-visit and two-visit strategies were respectively applied to investigate the incidence of hypertension in a cohort study.
  • In addition, by these two strategies, a cross-sectional study based on CHNS 2006 and CHNS 2006–2009/2011 was used to investigate the prevalence of hypertension.
  • If the two-visit strategy was applied to China hypertension survey, the hypertension burden was predicted to be overestimated by 25.5%–47.8% (based on JNC 7) and 23.5%–48.2% (based on the 2017 ACC/AHA), respectively.
Heated Tobacco Products Have Reached Younger or More Affluent People in Japan
  • New tobacco products are being diffused worldwide, and heated tobacco products (HTPs) have become widely available.
  • The spread of HTPs and the characteristics of their users must be studied to monitor tobacco control efforts.
  • This study examined the sociodemographic characteristics of HTPs users in Japan.
  • HTPs were accepted by younger or more affluent people.
Adherence to the Japanese Physical Activity Guideline During Early Childhood Among Rural Preschoolers: A Cross-sectional Study
  • Two-thirds of the preschoolers (66.2%) adhered to the levels of physical activity recommended by the Japanese guideline.
  • Boys (70.2%) had higher proportions of adherence to the Japanese physical activity guideline as compared to girls (61.2%).
  • Adherence to the Japanese physical activity guideline varied considerably among the 20 enrolled preschools (14–100%).
  • There were no significant differences in the proportions of adherence to the physical activity guideline among different preschool grades.
Association Between Area-level Risk of Job Instability and Workers’ Health: A Multi-level Analysis Using Population-based Survey Data From Japan
  • Association between area-level job instability and workers’ health was examined.
  • Workers’ health is negatively associated with a proportion of precarious employees.
  • Area-level job insecurity is more important for men, compared with women.
  • Adverse impact of precarious employment on health should be reduced.
Intakes of Specific Categories of Vegetables and Fruits Are Inversely Associated With Depressive Symptoms Among Adults
  • Current evidence between different types of vegetables or fruits intakes and depressive symptoms in the general population is completely unknown.
  • Tomatoes and tomato mixtures, dark-green, and other vegetables intakes were inversely related to depressive symptoms in the general population.
  • Berries and dried fruits intakes were inversely related to depressive symptoms in the general population.
  • An L-shaped relationship was observed between intake of total vegetables and depressive symptoms in the general population.
  • Intake of total fruits and depressive symptoms presented a linear inverse trend in the general population.
Review Article
Economic Evaluations of Gestational Diabetes Mellitus Screening: A Systematic Review
  • GDM screening generally found to be cost-effective, though uncertainties remain due to many factors.
  • The 1-step GDM screening, with more cases detected, is more likely to be cost-effective than the 2-step GDM screening.
  • Universal screening is more likely to be cost-effective than screening targeting the high-risk population.
Statistical Data
Clinical Trajectories of Suicide Attempts and Self-harm in Patients Admitted to Acute-care Hospitals in Japan: A Nationwide Inpatient Database Study
  • We described patient characteristics and clinical management for suicide attempts and self-harm among patients admitted to acute-care hospitals in Japan.
  • Of 17,881 patients admitted to acute-care hospitals in Japan with suicide attempts/self-harm during the study period, 2,639 (15%) completed suicide.
  • Among patients discharged to home, 51% did not receive psychiatric intervention.
  • In 468 (54%) acute-care hospitals, no psychiatric intervention was provided for suicide attempters during the study period.
  • Half of acute-care hospitals did not provide hospital-based psychiatric care for patients with suicide attempts or self-harm.


Volume 31, Issue 2 (February 2021)

The Major Source of Antioxidants Intake From Typical Diet Among Rural Farmers in North-eastern Japan in the 1990s
  • This is the first study to clarify the total antioxidant intake reflecting the foods commonly consumed in a Japanese population.
  • We constructed an antioxidant database of foods representative of the typical Japanese diet using 12-day dietary records from Japanese.
  • To consider the effects of peroxyl radical-scavenging activities, our database measured hydrophilic- and lipophilic antioxidant values on standardized methods.
  • We found that Japanese diet included rice and seafood, is a desirable diet with high in antioxidants, especially high in lipophilic antioxidants.
The Association Between Habitual Sleep Duration and Mortality According to Sex and Age: The Japan Public Health Center-based Prospective Study
  • Sleep durations ≥8 hours are associated with mortality from all-cause, CVD, and other causes in the Japanese general population.
  • Sex does not appear to be an effect modifier for the association between sleep duration and mortality outcomes.
  • Age with a cut-off at 50 years may be an effect modifier for the association between sleep duration and the risk of other-cause mortality in women.
Relationship Between Calcium Intake and Impaired Activities of Daily Living in a Japanese Population: NIPPON DATA90
  • In this nested case control study, the risk of impaired ADL assessed in 2000 was inversely associated with calcium intake assessed in 1990.
  • This inverse relationship was confirmed using bootstrap analyses which enabled to minimize the sampling bias.
Longitudinal Trends in Blood Pressure Associated With the Frequency of Laughter: The Circulatory Risk in Communities Study (CIRCS), a Longitudinal Study of the Japanese General Population
  • The frequency of laughter has known to been associated with cardiovascular disease and related biomarkers.
  • Although various mechanisms have accounted for the association between laughter and cardiovascular disease and related biomarkers, no previous studies have examined the association between laughter and changes in blood pressure levels.
  • Middle-aged men with low frequency of laughter had significantly increased systolic and diastolic blood pressure levels over the four-year period.
  • The changes in blood pressure associated with infrequent laughter were more evident in men without antihypertensive medication use over four years and men with a current drinking status at the baseline.
Seasonal Variation in Epidemiology of Kawasaki Disease-Related Coronary Artery Abnormalities in Japan, 1999–2017
  • The interaction between patient age and sex influences the development of Kawasaki disease (KD)-related coronary artery abnormalities (CAAs).
  • KD occurrence in summer/autumn was higher in younger than in older participants.
  • The lowest age group (<6 months) showed an inverse summer/autumn to winter/spring ratio (>1.0).
  • Female (<6 months) and male patients (≥5 years) have high risk for KD-related CAAs.
Estimated Prevalence of Cronkhite-Canada Syndrome, Chronic Enteropathy Associated With SLCO2A1 Gene, and Intestinal Behçet’s Disease in Japan in 2017: A Nationwide Survey
  • Cronkhite–Canada syndrome (CCS), chronic enteropathy associated with SLCO2A1 gene (CEAS), and intestinal Behçet’s disease (BD) are rare intractable intestinal disorders.
  • We conducted the first nationwide survey of these three diseases to estimate the prevalence of patients in Japan.
  • The estimated prevalence rates per 1,000,000 population of patients with CCS, CEAS, and intestinal BD were 3.7, 3.1, and 24.8, respectively, and found to be higher than those previously reported.
Statistical Data
Who Smokes in Europe? Data From 12 European Countries in the TackSHS Survey (2017–2018)
  • In Europe, 25.9% of adults are current smokers (31.0% among men and 21.2% among women).
  • Smoking prevalence substantially varies by country, ranging from 18.9% in Italy to 37.0% in Bulgaria.
  • Lower socio-economic status is a major determinant of smoking habit for both men and women.
Statistical Data
Excess mortality from suicide during the early COVID-19 pandemic period in Japan: a time-series modeling before the pandemic
  • Excess mortality from suicide was discussed to assess the impact of the COVID-19 pandemic in Japan.
  • Excess mortality during the pandemic period was estimated using a time series model based on the number of suicides before the pandemic.
  • No significant excess mortality was observed through the early pandemic period; instead, a downward trend in suicides for both sexes was visible.
  • Our results suggest that various changes in the early period of the COVID-19 pandemic induced a decrease in suicides in Japan.
Study Profile
Impact of Methylmercury and Other Heavy Metals Exposure on Neurocognitive Function in Children Aged 7 Years: Study Protocol of the Follow-up
  • Low-level heavy metals exposure could affect child neurodevelopment.
  • Data collection in different samples and at different timing can improve the sensitivity of associations between metals exposure and child neurodevelopment.
  • Polymorphisms could modulate the effects of metals at low exposure.


Volume 31, Issue 1 (January 2021)

Special Article
History and Profile of Diagnosis Procedure Combination (DPC): Development of a Real Data Collection System for Acute Inpatient Care in Japan
  • Diagnosis Procedure Combination is a patient classification method that was developed in Japan.
  • Diagnosis Procedure Combination was developed in order to standardize, evaluate, and improve Japanese medical care.
  • Many studies have used data from the Diagnosis Procedure Combination due to its detailed information.
Impact of PSCA Polymorphisms on the Risk of Duodenal Ulcer
  • We evaluated the association between PSCA polymorphisms and risk of duodenal/gastric ulcer and its interaction with environmental factors in a Japanese population.
  • Our study confirms an association between the PSCA rs2294008 C-allele and risk of duodenal ulcer in a large Japanese population.
  • This association was independent of age, sex, study site, smoking habit, drinking habit, and H. pylori status.
Intake of Vegetables and Fruits and the Risk of Cataract Incidence in a Japanese Population: The Japan Public Health Center-Based Prospective Study
  • The analysis considered the association between vegetable and fruit intake and cataract by sex in a Japanese population.
  • Vegetable intake was associated with decreased risk of cataract in men, but not women.
  • No association was found between fruit intake and cataract incidence in either sex.
Alcohol Consumption and Risk of Gastric Cancer: The Japan Collaborative Cohort Study
  • This is a prospective cohort study examine the sex-specific dose-response association between alcohol consumption and risk of gastric cancer among Japanese men and women.
  • We also evaluated the association between alcohol consumption and the site-specific risk of gastric cancer.
  • This study also discussed the differences from previous studies in Japan.
  • The present study suggested that alcohol consumption increases the risk of gastric cancer among Japanese men, regardless of anatomical sub-site of the cancer.
Effect of Dietary Nori (Dried Laver) on Blood Pressure in Young Japanese Children: An Intervention Study
  • Nori (dried laver) is an edible seaweed widely consumed in Japan.
  • Experimental studies have reported that seaweed has a hypotensive effect.
  • This intervention study examined the effect of nori intake on blood pressure.
  • Nori intake lowered diastolic blood pressure in boys aged 4 to 5 years.
  • Seaweed intake might have preventive effects on hypertension.
Infant Mortality Rates for Farming and Unemployed Households in the Japanese Prefectures: An Ecological Time Trend Analysis, 1999–2017
  • Compared to the infant mortality rate of the most privileged occupation type (type II regular worker), overall IMRs during the 1999-2017 period nearly doubled (1.96) among farming households and increased 6.5 times among unemployed households.
  • Inequality in IMRs across household occupations increased during the period of 1999-2017.
  • Inequality tended to be lower in the prefectures where population density was low, or farm density was high.
Hospital Surgical Volume and 3-Year Mortality in Severe Prognosis Cancers: A Population-Based Study Using Cancer Registry Data
  • Three-year mortality was significantly higher at low-volume hospitals (adjusted hazard ratio: 1.5-1.9) than high-volume for esophageal, biliary tract, and pancreatic cancers.
  • Moreover, mortality was significantly higher at middle-volume hospitals showing adjusted hazard ratio of 1.3-1.4 than high-volume for these cancers.
  • In particular localized pancreatic cancer, the impact of hospital surgical volume on 3-year mortality was strong (adjusted hazard ratio: 2.66).
The Level of Urine Dipstick Proteinuria and Its Relation to the Risk of Incident Cholelithiasis
  • Groups with more urine dipstick proteinuria had the worse clinical condition.
  • Urine dipstick proteinuria of 2+ or greater was significantly associated with the increased risk of incident cholelithiasis.
  • As far as we know, this is the first retrospective cohort study to evaluate the association between urine dipstick proteinuria and incident cholelithiasis.
Study Profile
Study Profile of the Tohoku Medical Megabank Community-Based Cohort Study
  • After the Great East Japan Earthquake, TMM CommCohort Study was established and 87,866 residents agreed to be enrolled.
  • Mainly two recruit methods were applied, i.e., health check-up based and assessment center based recruit.
  • The age-adjusted rates of current smoking and higher degrees of psychological distress were greater among residents living in coastal rather than among those in the inland areas.
Study Profile
Adachi Child Health Impact of Living Difficulty (A-CHILD) Study: Research Protocol and Profiles of Participants
  • Describing the purpose and design of the Adachi Child Health Impact and Living Difficulty (A-CHILD) study and the baseline profiles of participants.
  • A-CHILD study has been conducted since 2015 to clarify the associations between socioeconomic factors and child health.
  • The number of households in “living difficulties”, such as low household income or material deprivation, stood at 1,047 (24.5%).
  • This longitudinal study will continue to contribute important information for the development of policies to tackle the issue of child poverty.